This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Speech-sound disorder (SSD) is a complex behavioral disorder characterized by speech-sound production errors associated with deficits in articulation, phonological processes, and cognitive linguistic processes. SSD is prevalent in childhood and is comorbid with disorders of language, spelling, and reading disability, or dyslexia. Previous research suggests that developmental problems in domains associated with speech and language acquisition place a child at risk for dyslexia. Recent genetic studies have identified several candidate regions for dyslexia, including one on chromosome 3 segregating in a large Finnish pedigree. To explore common genetic influences on SSD and reading, we have conducted linkage analysis of regions previously linked to dyslexia. We have found that quantitative traits related to phonological memory, vocabulary, speech-sound production, and phonological representation are linked to regions on chromosomes 1, 3, 6, and 15. These results suggest that domains common to SSD and dyslexia are pleiotropically influenced influenced by loci in those chromosomal regions. Recently, we have completed genotyping of an Affymetrix 250k SNP chip in a subset of these families ascertained through a child with SSD. Our future plans include analyzing these genome-wide association data as well as new candidate gene SNP data. In addition, we plan structural equation modeling analyses to disentangle the relationship between pre-school speech-sound endophenotypes, school-age reading measures, and associated candidate genes.